Change CREATE STATISTICS syntax

Previously, we had the WITH clause in the middle of the command, where
you'd specify both generic options as well as statistic types.  Few
people liked this, so this commit changes it to remove the WITH keyword
from that clause and makes it accept statistic types only.  (We
currently don't have any generic options, but if we invent in the
future, we will gain a new WITH clause, probably at the end of the
command).

Also, the column list is now specified without parens, which makes the
whole command look more similar to a SELECT command.  This change will
let us expand the command to supporting expressions (not just columns
names) as well as multiple tables and their join conditions.

Tom added lots of code comments and fixed some parts of the CREATE
STATISTICS reference page, too; more changes in this area are
forthcoming.  He also fixed a potential problem in the alter_generic
regression test, reducing verbosity on a cascaded drop to avoid
dependency on message ordering, as we do in other tests.

Tom also closed a security bug: we documented that table ownership was
required in order to create a statistics object on it, but didn't
actually implement it.

Implement tab-completion for statistics objects.  This can stand some
more improvement.

Authors: Alvaro Herrera, with lots of cleanup by Tom Lane
Discussion: https://postgr.es/m/20170420212426.ltvgyhnefvhixm6i@alvherre.pgsql

21 files changed, 321 insertions, 286 deletions

diff --git a/doc/src/sgml/perform.sgml b/doc/src/sgml/perform.sgml
index b10b734b90..32e17ee5f8 100644
--- a/doc/src/sgml/perform.sgml
+++ b/doc/src/sgml/perform.sgml
@@ -1132,8 +1132,8 @@ WHERE tablename = 'road';
      To inspect functional dependencies on a statistics
      <literal>stts</literal>, you may do this:
 <programlisting>
-CREATE STATISTICS stts WITH (dependencies)
-               ON (zip, city) FROM zipcodes;
+CREATE STATISTICS stts (dependencies)
+               ON zip, city FROM zipcodes;
 ANALYZE zipcodes;
 SELECT stxname, stxkeys, stxdependencies
   FROM pg_statistic_ext
@@ -1219,8 +1219,8 @@ EXPLAIN (ANALYZE, TIMING OFF) SELECT * FROM t WHERE a = 1 AND b = 10;
      Continuing the above example, the n-distinct coefficients in a ZIP
      code table may look like the following:
 <programlisting>
-CREATE STATISTICS stts2 WITH (ndistinct)
-               ON (zip, state, city) FROM zipcodes;
+CREATE STATISTICS stts2 (ndistinct)
+               ON zip, state, city FROM zipcodes;
 ANALYZE zipcodes;
 SELECT stxkeys AS k, stxndistinct AS nd
   FROM pg_statistic_ext
diff --git a/doc/src/sgml/planstats.sgml b/doc/src/sgml/planstats.sgml
index 11580bfd22..ef847b9633 100644
--- a/doc/src/sgml/planstats.sgml
+++ b/doc/src/sgml/planstats.sgml
@@ -526,7 +526,7 @@ EXPLAIN (ANALYZE, TIMING OFF) SELECT * FROM t WHERE a = 1 AND b = 1;
     multivariate statistics on the two columns:
 
 <programlisting>
-CREATE STATISTICS stts WITH (dependencies) ON (a, b) FROM t;
+CREATE STATISTICS stts (dependencies) ON a, b FROM t;
 ANALYZE t;
 EXPLAIN (ANALYZE, TIMING OFF) SELECT * FROM t WHERE a = 1 AND b = 1;
                                   QUERY PLAN                                   
@@ -569,7 +569,7 @@ EXPLAIN (ANALYZE, TIMING OFF) SELECT COUNT(*) FROM t GROUP BY a, b;
     calculation, the estimate is much improved:
 <programlisting>
 DROP STATISTICS stts;
-CREATE STATISTICS stts WITH (dependencies, ndistinct) ON (a, b) FROM t;
+CREATE STATISTICS stts (dependencies, ndistinct) ON a, b FROM t;
 ANALYZE t;
 EXPLAIN (ANALYZE, TIMING OFF) SELECT COUNT(*) FROM t GROUP BY a, b;
                                        QUERY PLAN                                        
diff --git a/doc/src/sgml/ref/alter_statistics.sgml b/doc/src/sgml/ref/alter_statistics.sgml
index 3e4d28614a..4f25669852 100644
--- a/doc/src/sgml/ref/alter_statistics.sgml
+++ b/doc/src/sgml/ref/alter_statistics.sgml
@@ -17,7 +17,7 @@ PostgreSQL documentation
  <refnamediv>
   <refname>ALTER STATISTICS</refname>
   <refpurpose>
-   change the definition of a extended statistics
+   change the definition of an extended statistics object
   </refpurpose>
  </refnamediv>
 
@@ -34,19 +34,20 @@ ALTER STATISTICS <replaceable class="parameter">name</replaceable> SET SCHEMA <r
 
   <para>
    <command>ALTER STATISTICS</command> changes the parameters of an existing
-   extended statistics.  Any parameters not specifically set in the
+   extended statistics object.  Any parameters not specifically set in the
    <command>ALTER STATISTICS</command> command retain their prior settings.
   </para>
 
   <para>
-   You must own the statistics to use <command>ALTER STATISTICS</>.
-   To change a statistics' schema, you must also have <literal>CREATE</>
-   privilege on the new schema.
+   You must own the statistics object to use <command>ALTER STATISTICS</>.
+   To change a statistics object's schema, you must also
+   have <literal>CREATE</> privilege on the new schema.
    To alter the owner, you must also be a direct or indirect member of the new
    owning role, and that role must have <literal>CREATE</literal> privilege on
-   the statistics' schema.  (These restrictions enforce that altering the owner
-   doesn't do anything you couldn't do by dropping and recreating the statistics.
-   However, a superuser can alter ownership of any statistics anyway.)
+   the statistics object's schema.  (These restrictions enforce that altering
+   the owner doesn't do anything you couldn't do by dropping and recreating
+   the statistics object.  However, a superuser can alter ownership of any
+   statistics object anyway.)
   </para>
  </refsect1>
 
@@ -59,7 +60,8 @@ ALTER STATISTICS <replaceable class="parameter">name</replaceable> SET SCHEMA <r
       <term><replaceable class="parameter">name</replaceable></term>
       <listitem>
        <para>
-        The name (optionally schema-qualified) of the statistics to be altered.
+        The name (optionally schema-qualified) of the statistics object to be
+        altered.
        </para>
       </listitem>
      </varlistentry>
@@ -68,7 +70,7 @@ ALTER STATISTICS <replaceable class="parameter">name</replaceable> SET SCHEMA <r
       <term><replaceable class="PARAMETER">new_owner</replaceable></term>
       <listitem>
        <para>
-        The user name of the new owner of the statistics.
+        The user name of the new owner of the statistics object.
        </para>
       </listitem>
      </varlistentry>
@@ -77,7 +79,7 @@ ALTER STATISTICS <replaceable class="parameter">name</replaceable> SET SCHEMA <r
       <term><replaceable class="parameter">new_name</replaceable></term>
       <listitem>
        <para>
-        The new name for the statistics.
+        The new name for the statistics object.
        </para>
       </listitem>
      </varlistentry>
@@ -86,7 +88,7 @@ ALTER STATISTICS <replaceable class="parameter">name</replaceable> SET SCHEMA <r
       <term><replaceable class="parameter">new_schema</replaceable></term>
       <listitem>
        <para>
-        The new schema for the statistics.
+        The new schema for the statistics object.
        </para>
       </listitem>
      </varlistentry>
@@ -99,7 +101,7 @@ ALTER STATISTICS <replaceable class="parameter">name</replaceable> SET SCHEMA <r
   <title>Compatibility</title>
 
   <para>
-   There's no <command>ALTER STATISTICS</command> command in the SQL standard.
+   There is no <command>ALTER STATISTICS</command> command in the SQL standard.
   </para>
  </refsect1>
 
diff --git a/doc/src/sgml/ref/create_statistics.sgml b/doc/src/sgml/ref/create_statistics.sgml
index edbcf5840b..92ee4e4efa 100644
--- a/doc/src/sgml/ref/create_statistics.sgml
+++ b/doc/src/sgml/ref/create_statistics.sgml
@@ -22,8 +22,8 @@ PostgreSQL documentation
  <refsynopsisdiv>
 <synopsis>
 CREATE STATISTICS [ IF NOT EXISTS ] <replaceable class="PARAMETER">statistics_name</replaceable>
-    WITH ( <replaceable class="PARAMETER">option</replaceable> [= <replaceable class="PARAMETER">value</replaceable>] [, ... ] )
-    ON ( <replaceable class="PARAMETER">column_name</replaceable>, <replaceable class="PARAMETER">column_name</replaceable> [, ...])
+    [ ( <replaceable class="PARAMETER">statistic_type</replaceable> [, ... ] ) ]
+    ON <replaceable class="PARAMETER">column_name</replaceable>, <replaceable class="PARAMETER">column_name</replaceable> [, ...]
     FROM <replaceable class="PARAMETER">table_name</replaceable>
 </synopsis>
 
@@ -34,17 +34,17 @@ CREATE STATISTICS [ IF NOT EXISTS ] <replaceable class="PARAMETER">statistics_na
 
   <para>
    <command>CREATE STATISTICS</command> will create a new extended statistics
-   object on the specified table, foreign table or materialized view.
-   The statistics will be created in the current database and
-   will be owned by the user issuing the command.
+   object tracking data about the specified table, foreign table or
+   materialized view.  The statistics object will be created in the current
+   database and will be owned by the user issuing the command.
   </para>
 
   <para>
    If a schema name is given (for example, <literal>CREATE STATISTICS
-   myschema.mystat ...</>) then the statistics is created in the specified
-   schema.  Otherwise it is created in the current schema.  The name of
-   the statistics must be distinct from the name of any other statistics in the
-   same schema.
+   myschema.mystat ...</>) then the statistics object is created in the
+   specified schema.  Otherwise it is created in the current schema.
+   The name of the statistics object must be distinct from the name of any
+   other statistics object in the same schema.
   </para>
  </refsect1>
 
@@ -57,10 +57,10 @@ CREATE STATISTICS [ IF NOT EXISTS ] <replaceable class="PARAMETER">statistics_na
     <term><literal>IF NOT EXISTS</></term>
     <listitem>
      <para>
-      Do not throw an error if a statistics with the same name already exists.
-      A notice is issued in this case.  Note that only the name of the
-      statistics object is considered here. The definition of the statistics is
-      not considered.
+      Do not throw an error if a statistics object with the same name already
+      exists.  A notice is issued in this case.  Note that only the name of
+      the statistics object is considered here, not the details of its
+      definition.
      </para>
     </listitem>
    </varlistentry>
@@ -69,67 +69,45 @@ CREATE STATISTICS [ IF NOT EXISTS ] <replaceable class="PARAMETER">statistics_na
     <term><replaceable class="PARAMETER">statistics_name</replaceable></term>
     <listitem>
      <para>
-      The name (optionally schema-qualified) of the statistics to be created.
+      The name (optionally schema-qualified) of the statistics object to be
+      created.
      </para>
     </listitem>
    </varlistentry>
 
    <varlistentry>
-    <term><replaceable class="PARAMETER">column_name</replaceable></term>
+    <term><replaceable class="PARAMETER">statistic_type</replaceable></term>
     <listitem>
      <para>
-      The name of a column to be included in the statistics.
+      A statistic type to be computed in this statistics object.  Currently
+      supported types are <literal>ndistinct</literal>, which enables
+      n-distinct coefficient tracking,
+      and <literal>dependencies</literal>, which enables functional
+      dependencies.
      </para>
     </listitem>
    </varlistentry>
 
    <varlistentry>
-    <term><replaceable class="PARAMETER">table_name</replaceable></term>
-    <listitem>
-     <para>
-      The name (optionally schema-qualified) of the table the statistics should
-      be created on.
-     </para>
-    </listitem>
-   </varlistentry>
-
-  </variablelist>
-
-  <refsect2 id="SQL-CREATESTATISTICS-parameters">
-   <title id="SQL-CREATESTATISTICS-parameters-title">Parameters</title>
-
- <indexterm zone="sql-createstatistics-parameters">
-  <primary>statistics parameters</primary>
- </indexterm>
-
-   <para>
-    The <literal>WITH</> clause can specify <firstterm>options</>
-    for the statistics. Available options are listed below.
-   </para>
-
-   <variablelist>
-
-   <varlistentry>
-    <term><literal>dependencies</> (<type>boolean</>)</term>
+    <term><replaceable class="PARAMETER">column_name</replaceable></term>
     <listitem>
      <para>
-      Enables functional dependencies for the statistics.
+      The name of a table column to be included in the statistics object.
      </para>
     </listitem>
    </varlistentry>
 
    <varlistentry>
-    <term><literal>ndistinct</> (<type>boolean</>)</term>
+    <term><replaceable class="PARAMETER">table_name</replaceable></term>
     <listitem>
      <para>
-      Enables ndistinct coefficients for the statistics.
+      The name (optionally schema-qualified) of the table containing the
+      column(s) the statistics are computed on.
      </para>
     </listitem>
    </varlistentry>
 
-   </variablelist>
-
-  </refsect2>
+  </variablelist>
  </refsect1>
 
  <refsect1>
@@ -158,7 +136,7 @@ CREATE TABLE t1 (
 INSERT INTO t1 SELECT i/100, i/500
                  FROM generate_series(1,1000000) s(i);
 
-CREATE STATISTICS s1 WITH (dependencies) ON (a, b) FROM t1;
+CREATE STATISTICS s1 (dependencies) ON a, b FROM t1;
 
 ANALYZE t1;
 
@@ -168,6 +146,11 @@ EXPLAIN ANALYZE SELECT * FROM t1 WHERE (a = 1) AND (b = 0);
 -- invalid combination of values
 EXPLAIN ANALYZE SELECT * FROM t1 WHERE (a = 1) AND (b = 1);
 </programlisting>
+
+   Without functional-dependency statistics, the planner would make the
+   same estimate of the number of matching rows for these two queries.
+   With such statistics, it is able to tell that one case has matches
+   and the other does not.
   </para>
 
  </refsect1>
@@ -176,7 +159,7 @@ EXPLAIN ANALYZE SELECT * FROM t1 WHERE (a = 1) AND (b = 1);
   <title>Compatibility</title>
 
   <para>
-   There's no <command>CREATE STATISTICS</command> command in the SQL standard.
+   There is no <command>CREATE STATISTICS</command> command in the SQL standard.
   </para>
  </refsect1>
 
diff --git a/doc/src/sgml/ref/drop_statistics.sgml b/doc/src/sgml/ref/drop_statistics.sgml
index 98c338182b..ef659fca61 100644
--- a/doc/src/sgml/ref/drop_statistics.sgml
+++ b/doc/src/sgml/ref/drop_statistics.sgml
@@ -29,9 +29,9 @@ DROP STATISTICS [ IF EXISTS ] <replaceable class="PARAMETER">name</replaceable>
   <title>Description</title>
 
   <para>
-   <command>DROP STATISTICS</command> removes statistics from the database.
-   Only the statistics owner, the schema owner, and superuser can drop a
-   statistics.
+   <command>DROP STATISTICS</command> removes statistics object(s) from the
+   database.  Only the statistics object's owner, the schema owner, or a
+   superuser can drop a statistics object.
   </para>
 
  </refsect1>
@@ -44,8 +44,8 @@ DROP STATISTICS [ IF EXISTS ] <replaceable class="PARAMETER">name</replaceable>
     <term><literal>IF EXISTS</literal></term>
     <listitem>
      <para>
-      Do not throw an error if the statistics do not exist. A notice is
-      issued in this case.
+      Do not throw an error if the statistics object does not exist. A notice
+      is issued in this case.
      </para>
     </listitem>
    </varlistentry>
@@ -54,7 +54,7 @@ DROP STATISTICS [ IF EXISTS ] <replaceable class="PARAMETER">name</replaceable>
     <term><replaceable class="PARAMETER">name</replaceable></term>
     <listitem>
      <para>
-      The name (optionally schema-qualified) of the statistics to drop.
+      The name (optionally schema-qualified) of the statistics object to drop.
      </para>
     </listitem>
    </varlistentry>
@@ -66,7 +66,7 @@ DROP STATISTICS [ IF EXISTS ] <replaceable class="PARAMETER">name</replaceable>
   <title>Examples</title>
 
   <para>
-   To destroy two statistics objects on different schemas, without failing
+   To destroy two statistics objects in different schemas, without failing
    if they don't exist:
 
 <programlisting>
@@ -82,7 +82,7 @@ DROP STATISTICS IF EXISTS
   <title>Compatibility</title>
 
   <para>
-   There's no <command>DROP STATISTICS</command> command in the SQL standard.
+   There is no <command>DROP STATISTICS</command> command in the SQL standard.
   </para>
  </refsect1>
 
diff --git a/src/backend/commands/statscmds.c b/src/backend/commands/statscmds.c
index 0b9c33e30a..662b4fa15d 100644
--- a/src/backend/commands/statscmds.c
+++ b/src/backend/commands/statscmds.c
@@ -60,7 +60,7 @@ CreateStatistics(CreateStatsStmt *stmt)
 	bool		nulls[Natts_pg_statistic_ext];
 	int2vector *stxkeys;
 	Relation	statrel;
-	Relation	rel;
+	Relation	rel = NULL;
 	Oid			relid;
 	ObjectAddress parentobject,
 				childobject;
@@ -71,7 +71,7 @@ CreateStatistics(CreateStatsStmt *stmt)
 	bool		build_dependencies;
 	bool		requested_type = false;
 	int			i;
-	ListCell   *l;
+	ListCell   *cell;
 
 	Assert(IsA(stmt, CreateStatsStmt));
 
@@ -101,35 +101,81 @@ CreateStatistics(CreateStatsStmt *stmt)
 	}
 
 	/*
-	 * CREATE STATISTICS will influence future execution plans but does not
-	 * interfere with currently executing plans.  So it should be enough to
-	 * take only ShareUpdateExclusiveLock on relation, conflicting with
-	 * ANALYZE and other DDL that sets statistical information, but not with
-	 * normal queries.
+	 * Examine the FROM clause.  Currently, we only allow it to be a single
+	 * simple table, but later we'll probably allow multiple tables and JOIN
+	 * syntax.  The grammar is already prepared for that, so we have to check
+	 * here that what we got is what we can support.
 	 */
-	rel = relation_openrv(stmt->relation, ShareUpdateExclusiveLock);
-	relid = RelationGetRelid(rel);
-
-	if (rel->rd_rel->relkind != RELKIND_RELATION &&
-		rel->rd_rel->relkind != RELKIND_MATVIEW &&
-		rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
-		rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
+	if (list_length(stmt->relations) != 1)
 		ereport(ERROR,
-				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
-				 errmsg("relation \"%s\" is not a table, foreign table, or materialized view",
-						RelationGetRelationName(rel))));
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+		  errmsg("only a single relation is allowed in CREATE STATISTICS")));
+
+	foreach(cell, stmt->relations)
+	{
+		Node	   *rln = (Node *) lfirst(cell);
+
+		if (!IsA(rln, RangeVar))
+			ereport(ERROR,
+					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+					 errmsg("only a single relation is allowed in CREATE STATISTICS")));
+
+		/*
+		 * CREATE STATISTICS will influence future execution plans but does
+		 * not interfere with currently executing plans.  So it should be
+		 * enough to take only ShareUpdateExclusiveLock on relation,
+		 * conflicting with ANALYZE and other DDL that sets statistical
+		 * information, but not with normal queries.
+		 */
+		rel = relation_openrv((RangeVar *) rln, ShareUpdateExclusiveLock);
+
+		/* Restrict to allowed relation types */
+		if (rel->rd_rel->relkind != RELKIND_RELATION &&
+			rel->rd_rel->relkind != RELKIND_MATVIEW &&
+			rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
+			rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
+			ereport(ERROR,
+					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+					 errmsg("relation \"%s\" is not a table, foreign table, or materialized view",
+							RelationGetRelationName(rel))));
+
+		/* You must own the relation to create stats on it */
+		if (!pg_class_ownercheck(RelationGetRelid(rel), GetUserId()))
+			aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS,
+						   RelationGetRelationName(rel));
+	}
+
+	Assert(rel);
+	relid = RelationGetRelid(rel);
 
 	/*
-	 * Transform column names to array of attnums. While at it, enforce some
-	 * constraints.
+	 * Currently, we only allow simple column references in the expression
+	 * list.  That will change someday, and again the grammar already supports
+	 * it so we have to enforce restrictions here.  For now, we can convert
+	 * the expression list to a simple array of attnums.  While at it, enforce
+	 * some constraints.
 	 */
-	foreach(l, stmt->keys)
+	foreach(cell, stmt->exprs)
 	{
-		char	   *attname = strVal(lfirst(l));
+		Node	   *expr = (Node *) lfirst(cell);
+		ColumnRef  *cref;
+		char	   *attname;
 		HeapTuple	atttuple;
 		Form_pg_attribute attForm;
 		TypeCacheEntry *type;
 
+		if (!IsA(expr, ColumnRef))
+			ereport(ERROR,
+					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+					 errmsg("only simple column references are allowed in CREATE STATISTICS")));
+		cref = (ColumnRef *) expr;
+
+		if (list_length(cref->fields) != 1)
+			ereport(ERROR,
+					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+					 errmsg("only simple column references are allowed in CREATE STATISTICS")));
+		attname = strVal((Value *) linitial(cref->fields));
+
 		atttuple = SearchSysCacheAttName(relid, attname);
 		if (!HeapTupleIsValid(atttuple))
 			ereport(ERROR,
@@ -194,30 +240,29 @@ CreateStatistics(CreateStatsStmt *stmt)
 	stxkeys = buildint2vector(attnums, numcols);
 
 	/*
-	 * Parse the statistics options.  Currently only statistics types are
-	 * recognized.
+	 * Parse the statistics types.
 	 */
 	build_ndistinct = false;
 	build_dependencies = false;
-	foreach(l, stmt->options)
+	foreach(cell, stmt->stat_types)
 	{
-		DefElem    *opt = (DefElem *) lfirst(l);
+		char	   *type = strVal((Value *) lfirst(cell));
 
-		if (strcmp(opt->defname, "ndistinct") == 0)
+		if (strcmp(type, "ndistinct") == 0)
 		{
-			build_ndistinct = defGetBoolean(opt);
+			build_ndistinct = true;
 			requested_type = true;
 		}
-		else if (strcmp(opt->defname, "dependencies") == 0)
+		else if (strcmp(type, "dependencies") == 0)
 		{
-			build_dependencies = defGetBoolean(opt);
+			build_dependencies = true;
 			requested_type = true;
 		}
 		else
 			ereport(ERROR,
 					(errcode(ERRCODE_SYNTAX_ERROR),
-					 errmsg("unrecognized STATISTICS option \"%s\"",
-							opt->defname)));
+					 errmsg("unrecognized statistics type \"%s\"",
+							type)));
 	}
 	/* If no statistic type was specified, build them all. */
 	if (!requested_type)
@@ -268,6 +313,8 @@ CreateStatistics(CreateStatsStmt *stmt)
 
 	/*
 	 * Add a dependency on the table, so that stats get dropped on DROP TABLE.
+	 *
+	 * XXX don't we need dependencies on the specific columns, instead?
 	 */
 	ObjectAddressSet(parentobject, RelationRelationId, relid);
 	ObjectAddressSet(childobject, StatisticExtRelationId, statoid);
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index 2d2a9d00b7..d13a6fc03f 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -3389,9 +3389,9 @@ _copyCreateStatsStmt(const CreateStatsStmt *from)
 	CreateStatsStmt *newnode = makeNode(CreateStatsStmt);
 
 	COPY_NODE_FIELD(defnames);
-	COPY_NODE_FIELD(relation);
-	COPY_NODE_FIELD(keys);
-	COPY_NODE_FIELD(options);
+	COPY_NODE_FIELD(stat_types);
+	COPY_NODE_FIELD(exprs);
+	COPY_NODE_FIELD(relations);
 	COPY_SCALAR_FIELD(if_not_exists);
 
 	return newnode;
diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c
index b5459cd726..c9a8c34892 100644
--- a/src/backend/nodes/equalfuncs.c
+++ b/src/backend/nodes/equalfuncs.c
@@ -1349,9 +1349,9 @@ static bool
 _equalCreateStatsStmt(const CreateStatsStmt *a, const CreateStatsStmt *b)
 {
 	COMPARE_NODE_FIELD(defnames);
-	COMPARE_NODE_FIELD(relation);
-	COMPARE_NODE_FIELD(keys);
-	COMPARE_NODE_FIELD(options);
+	COMPARE_NODE_FIELD(stat_types);
+	COMPARE_NODE_FIELD(exprs);
+	COMPARE_NODE_FIELD(relations);
 	COMPARE_SCALAR_FIELD(if_not_exists);
 
 	return true;
diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index 98f67681a7..3d5b09aeee 100644
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -2639,9 +2639,9 @@ _outCreateStatsStmt(StringInfo str, const CreateStatsStmt *node)
 	WRITE_NODE_TYPE("CREATESTATSSTMT");
 
 	WRITE_NODE_FIELD(defnames);
-	WRITE_NODE_FIELD(relation);
-	WRITE_NODE_FIELD(keys);
-	WRITE_NODE_FIELD(options);
+	WRITE_NODE_FIELD(stat_types);
+	WRITE_NODE_FIELD(exprs);
+	WRITE_NODE_FIELD(relations);
 	WRITE_BOOL_FIELD(if_not_exists);
 }
 
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index d04bb7ea3e..28223311e6 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -3835,31 +3835,29 @@ ExistingIndex:   USING INDEX index_name				{ $$ = $3; }
 /*****************************************************************************
  *
  *		QUERY :
- *				CREATE STATISTICS stats_name WITH (options) ON (columns) FROM relname
+ *				CREATE STATISTICS stats_name [(stat types)]
+ *					ON expression-list FROM from_list
+ *
+ * Note: the expectation here is that the clauses after ON are a subset of
+ * SELECT syntax, allowing for expressions and joined tables, and probably
+ * someday a WHERE clause.  Much less than that is currently implemented,
+ * but the grammar accepts it and then we'll throw FEATURE_NOT_SUPPORTED
+ * errors as necessary at execution.
  *
  *****************************************************************************/
 
-
-CreateStatsStmt:	CREATE STATISTICS any_name opt_reloptions ON '(' columnList ')' FROM qualified_name
-						{
-							CreateStatsStmt *n = makeNode(CreateStatsStmt);
-							n->defnames = $3;
-							n->relation = $10;
-							n->keys = $7;
-							n->options = $4;
-							n->if_not_exists = false;
-							$$ = (Node *)n;
-						}
-					| CREATE STATISTICS IF_P NOT EXISTS any_name opt_reloptions ON '(' columnList ')' FROM qualified_name
-						{
-							CreateStatsStmt *n = makeNode(CreateStatsStmt);
-							n->defnames = $6;
-							n->relation = $13;
-							n->keys = $10;
-							n->options = $7;
-							n->if_not_exists = true;
-							$$ = (Node *)n;
-						}
+CreateStatsStmt:
+			CREATE opt_if_not_exists STATISTICS any_name
+			opt_name_list ON expr_list FROM from_list
+				{
+					CreateStatsStmt *n = makeNode(CreateStatsStmt);
+					n->defnames = $4;
+					n->stat_types = $5;
+					n->exprs = $7;
+					n->relations = $9;
+					n->if_not_exists = $2;
+					$$ = (Node *)n;
+				}
 			;
 
 /*****************************************************************************
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index cbde1fff01..983b9800cc 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -1504,15 +1504,15 @@ pg_get_statisticsext_worker(Oid statextid, bool missing_ok)
 	}
 
 	/*
-	 * If any option is disabled, then we'll need to append a WITH clause to
-	 * show which options are enabled.  We omit the WITH clause on purpose
+	 * If any option is disabled, then we'll need to append the types clause
+	 * to show which options are enabled.  We omit the types clause on purpose
 	 * when all options are enabled, so a pg_dump/pg_restore will create all
 	 * statistics types on a newer postgres version, if the statistics had all
 	 * options enabled on the original version.
 	 */
 	if (!ndistinct_enabled || !dependencies_enabled)
 	{
-		appendStringInfoString(&buf, " WITH (");
+		appendStringInfoString(&buf, " (");
 		if (ndistinct_enabled)
 			appendStringInfoString(&buf, "ndistinct");
 		else if (dependencies_enabled)
@@ -1521,7 +1521,7 @@ pg_get_statisticsext_worker(Oid statextid, bool missing_ok)
 		appendStringInfoChar(&buf, ')');
 	}
 
-	appendStringInfoString(&buf, " ON (");
+	appendStringInfoString(&buf, " ON ");
 
 	for (colno = 0; colno < statextrec->stxkeys.dim1; colno++)
 	{
@@ -1536,7 +1536,7 @@ pg_get_statisticsext_worker(Oid statextid, bool missing_ok)
 		appendStringInfoString(&buf, quote_identifier(attname));
 	}
 
-	appendStringInfo(&buf, ") FROM %s",
+	appendStringInfo(&buf, " FROM %s",
 					 generate_relation_name(statextrec->stxrelid, NIL));
 
 	ReleaseSysCache(statexttup);
diff --git a/src/bin/pg_dump/t/002_pg_dump.pl b/src/bin/pg_dump/t/002_pg_dump.pl
index b62299929f..9bd400e067 100644
--- a/src/bin/pg_dump/t/002_pg_dump.pl
+++ b/src/bin/pg_dump/t/002_pg_dump.pl
@@ -4955,9 +4955,9 @@ qr/CREATE TRANSFORM FOR integer LANGUAGE sql \(FROM SQL WITH FUNCTION pg_catalog
 		catch_all    => 'CREATE ... commands',
 		create_order => 97,
 		create_sql   => 'CREATE STATISTICS dump_test.test_ext_stats_no_options
-							ON (col1, col2) FROM dump_test.test_fifth_table',
+							ON col1, col2 FROM dump_test.test_fifth_table',
 		regexp => qr/^
-			\QCREATE STATISTICS dump_test.test_ext_stats_no_options ON (col1, col2) FROM test_fifth_table;\E
+			\QCREATE STATISTICS dump_test.test_ext_stats_no_options ON col1, col2 FROM test_fifth_table;\E
 		    /xms,
 		like => {
 			binary_upgrade          => 1,
@@ -4988,10 +4988,10 @@ qr/CREATE TRANSFORM FOR integer LANGUAGE sql \(FROM SQL WITH FUNCTION pg_catalog
 		all_runs     => 1,
 		catch_all    => 'CREATE ... commands',
 		create_order => 97,
-		create_sql   => 'CREATE STATISTICS dump_test.test_ext_stats_using
-							WITH (ndistinct) ON (col1, col2) FROM dump_test.test_fifth_table',
+		create_sql   => 'CREATE STATISTICS dump_test.test_ext_stats_opts
+							(ndistinct) ON col1, col2 FROM dump_test.test_fifth_table',
 		regexp => qr/^
-			\QCREATE STATISTICS dump_test.test_ext_stats_using WITH (ndistinct) ON (col1, col2) FROM test_fifth_table;\E
+			\QCREATE STATISTICS dump_test.test_ext_stats_opts (ndistinct) ON col1, col2 FROM test_fifth_table;\E
 		    /xms,
 		like => {
 			binary_upgrade          => 1,
diff --git a/src/bin/psql/describe.c b/src/bin/psql/describe.c
index 13395f5ca6..386af6168f 100644
--- a/src/bin/psql/describe.c
+++ b/src/bin/psql/describe.c
@@ -2355,8 +2355,9 @@ describeOneTableDetails(const char *schemaname,
 		{
 			printfPQExpBuffer(&buf,
 							  "SELECT oid, "
+							  "stxrelid::pg_catalog.regclass, "
 							  "stxnamespace::pg_catalog.regnamespace AS nsp, "
-							  "stxname, stxkeys,\n"
+							  "stxname,\n"
 							  "  (SELECT pg_catalog.string_agg(pg_catalog.quote_ident(attname),', ')\n"
 							  "   FROM pg_catalog.unnest(stxkeys) s(attnum)\n"
 							  "   JOIN pg_catalog.pg_attribute a ON (stxrelid = a.attrelid AND\n"
@@ -2385,9 +2386,9 @@ describeOneTableDetails(const char *schemaname,
 					printfPQExpBuffer(&buf, "    ");
 
 					/* statistics name (qualified with namespace) */
-					appendPQExpBuffer(&buf, "\"%s.%s\" WITH (",
-									  PQgetvalue(result, i, 1),
-									  PQgetvalue(result, i, 2));
+					appendPQExpBuffer(&buf, "\"%s\".\"%s\" (",
+									  PQgetvalue(result, i, 2),
+									  PQgetvalue(result, i, 3));
 
 					/* options */
 					if (strcmp(PQgetvalue(result, i, 5), "t") == 0)
@@ -2401,8 +2402,9 @@ describeOneTableDetails(const char *schemaname,
 						appendPQExpBuffer(&buf, "%sdependencies", gotone ? ", " : "");
 					}
 
-					appendPQExpBuffer(&buf, ") ON (%s)",
-									  PQgetvalue(result, i, 4));
+					appendPQExpBuffer(&buf, ") ON %s FROM %s",
+									  PQgetvalue(result, i, 4),
+									  PQgetvalue(result, i, 1));
 
 					printTableAddFooter(&cont, buf.data);
 				}
diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index 92abcc3ac3..09fb30f270 100644
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -616,6 +616,21 @@ static const SchemaQuery Query_for_list_of_matviews = {
 	NULL
 };
 
+static const SchemaQuery Query_for_list_of_statistics = {
+	/* catname */
+	"pg_catalog.pg_statistic_ext s",
+	/* selcondition */
+	NULL,
+	/* viscondition */
+	NULL,
+	/* namespace */
+	"s.stxnamespace",
+	/* result */
+	"pg_catalog.quote_ident(s.stxname)",
+	/* qualresult */
+	NULL
+};
+
 
 /*
  * Queries to get lists of names of various kinds of things, possibly
@@ -1023,6 +1038,7 @@ static const pgsql_thing_t words_after_create[] = {
 	{"SCHEMA", Query_for_list_of_schemas},
 	{"SEQUENCE", NULL, &Query_for_list_of_sequences},
 	{"SERVER", Query_for_list_of_servers},
+	{"STATISTICS", NULL, &Query_for_list_of_statistics},
 	{"SUBSCRIPTION", Query_for_list_of_subscriptions},
 	{"SYSTEM", NULL, NULL, THING_NO_CREATE | THING_NO_DROP},
 	{"TABLE", NULL, &Query_for_list_of_tables},
@@ -1782,6 +1798,10 @@ psql_completion(const char *text, int start, int end)
 	else if (Matches5("ALTER", "RULE", MatchAny, "ON", MatchAny))
 		COMPLETE_WITH_CONST("RENAME TO");
 
+	/* ALTER STATISTICS <name> */
+	else if (Matches3("ALTER", "STATISTICS", MatchAny))
+		COMPLETE_WITH_LIST3("OWNER TO", "RENAME TO", "SET SCHEMA");
+
 	/* ALTER TRIGGER <name>, add ON */
 	else if (Matches3("ALTER", "TRIGGER", MatchAny))
 		COMPLETE_WITH_CONST("ON");
@@ -2118,7 +2138,8 @@ psql_completion(const char *text, int start, int end)
 		{"ACCESS METHOD", "CAST", "COLLATION", "CONVERSION", "DATABASE",
 			"EVENT TRIGGER", "EXTENSION",
 			"FOREIGN DATA WRAPPER", "FOREIGN TABLE",
-			"SERVER", "INDEX", "LANGUAGE", "POLICY", "PUBLICATION", "RULE", "SCHEMA", "SEQUENCE", "SUBSCRIPTION",
+			"SERVER", "INDEX", "LANGUAGE", "POLICY", "PUBLICATION", "RULE",
+			"SCHEMA", "SEQUENCE", "STATISTICS", "SUBSCRIPTION",
 			"TABLE", "TYPE", "VIEW", "MATERIALIZED VIEW", "COLUMN", "AGGREGATE", "FUNCTION",
 			"OPERATOR", "TRIGGER", "CONSTRAINT", "DOMAIN", "LARGE OBJECT",
 		"TABLESPACE", "TEXT SEARCH", "ROLE", NULL};
@@ -2380,6 +2401,19 @@ psql_completion(const char *text, int start, int end)
 	else if (Matches3("CREATE", "SERVER", MatchAny))
 		COMPLETE_WITH_LIST3("TYPE", "VERSION", "FOREIGN DATA WRAPPER");
 
+/* CREATE STATISTICS <name> */
+	else if (Matches3("CREATE", "STATISTICS", MatchAny))
+		COMPLETE_WITH_LIST2("(", "ON");
+	else if (Matches4("CREATE", "STATISTICS", MatchAny, "("))
+		COMPLETE_WITH_LIST2("ndistinct", "dependencies");
+	else if (HeadMatches3("CREATE", "STATISTICS", MatchAny) &&
+			 previous_words[0][0] == '(' &&
+			 previous_words[0][strlen(previous_words[0]) - 1] == ')')
+		COMPLETE_WITH_CONST("ON");
+	else if (HeadMatches3("CREATE", "STATISTICS", MatchAny) &&
+			 TailMatches1("FROM"))
+		COMPLETE_WITH_SCHEMA_QUERY(Query_for_list_of_tables, NULL);
+
 /* CREATE TABLE --- is allowed inside CREATE SCHEMA, so use TailMatches */
 	/* Complete "CREATE TEMP/TEMPORARY" with the possible temp objects */
 	else if (TailMatches2("CREATE", "TEMP|TEMPORARY"))
@@ -2585,7 +2619,7 @@ psql_completion(const char *text, int start, int end)
 /* DROP */
 	/* Complete DROP object with CASCADE / RESTRICT */
 	else if (Matches3("DROP",
-					  "COLLATION|CONVERSION|DOMAIN|EXTENSION|LANGUAGE|PUBLICATION|SCHEMA|SEQUENCE|SERVER|SUBSCRIPTION|TABLE|TYPE|VIEW",
+					  "COLLATION|CONVERSION|DOMAIN|EXTENSION|LANGUAGE|PUBLICATION|SCHEMA|SEQUENCE|SERVER|SUBSCRIPTION|STATISTICS|TABLE|TYPE|VIEW",
 					  MatchAny) ||
 			 Matches4("DROP", "ACCESS", "METHOD", MatchAny) ||
 			 (Matches4("DROP", "AGGREGATE|FUNCTION", MatchAny, MatchAny) &&
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index 46c23c2530..d396be382b 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -2689,10 +2689,10 @@ typedef struct CreateStatsStmt
 {
 	NodeTag		type;
 	List	   *defnames;		/* qualified name (list of Value strings) */
-	RangeVar   *relation;		/* relation to build statistics on */
-	List	   *keys;			/* String nodes naming referenced columns */
-	List	   *options;		/* list of DefElem */
-	bool		if_not_exists;	/* do nothing if statistics already exists */
+	List	   *stat_types;		/* stat types (list of Value strings) */
+	List	   *exprs;			/* expressions to build statistics on */
+	List	   *relations;		/* rels to build stats on (list of RangeVar) */
+	bool		if_not_exists;	/* do nothing if stats name already exists */
 } CreateStatsStmt;
 
 /* ----------------------
diff --git a/src/test/regress/expected/alter_generic.out b/src/test/regress/expected/alter_generic.out
index a81a4edfb2..28e69166be 100644
--- a/src/test/regress/expected/alter_generic.out
+++ b/src/test/regress/expected/alter_generic.out
@@ -501,8 +501,8 @@ DROP OPERATOR FAMILY alt_opf18 USING btree;
 --
 SET SESSION AUTHORIZATION regress_alter_user1;
 CREATE TABLE alt_regress_1 (a INTEGER, b INTEGER);
-CREATE STATISTICS alt_stat1 ON (a, b) FROM alt_regress_1;
-CREATE STATISTICS alt_stat2 ON (a, b) FROM alt_regress_1;
+CREATE STATISTICS alt_stat1 ON a, b FROM alt_regress_1;
+CREATE STATISTICS alt_stat2 ON a, b FROM alt_regress_1;
 ALTER STATISTICS alt_stat1 RENAME TO alt_stat2;   -- failed (name conflict)
 ERROR:  statistics "alt_stat2" already exists in schema "alt_nsp1"
 ALTER STATISTICS alt_stat1 RENAME TO alt_stat3;   -- failed (name conflict)
@@ -511,8 +511,9 @@ ERROR:  must be member of role "regress_alter_user2"
 ALTER STATISTICS alt_stat2 OWNER TO regress_alter_user3;  -- OK
 ALTER STATISTICS alt_stat2 SET SCHEMA alt_nsp2;    -- OK
 SET SESSION AUTHORIZATION regress_alter_user2;
-CREATE STATISTICS alt_stat1 ON (a, b) FROM alt_regress_1;
-CREATE STATISTICS alt_stat2 ON (a, b) FROM alt_regress_1;
+CREATE TABLE alt_regress_2 (a INTEGER, b INTEGER);
+CREATE STATISTICS alt_stat1 ON a, b FROM alt_regress_2;
+CREATE STATISTICS alt_stat2 ON a, b FROM alt_regress_2;
 ALTER STATISTICS alt_stat3 RENAME TO alt_stat4;    -- failed (not owner)
 ERROR:  must be owner of statistics alt_stat3
 ALTER STATISTICS alt_stat1 RENAME TO alt_stat4;    -- OK
@@ -672,54 +673,13 @@ SELECT nspname, prsname
 ---
 --- Cleanup resources
 ---
+set client_min_messages to warning; -- suppress cascade notices
 DROP FOREIGN DATA WRAPPER alt_fdw2 CASCADE;
-NOTICE:  drop cascades to server alt_fserv2
 DROP FOREIGN DATA WRAPPER alt_fdw3 CASCADE;
-NOTICE:  drop cascades to server alt_fserv3
 DROP LANGUAGE alt_lang2 CASCADE;
 DROP LANGUAGE alt_lang3 CASCADE;
-DROP LANGUAGE alt_lang4 CASCADE;
-ERROR:  language "alt_lang4" does not exist
 DROP SCHEMA alt_nsp1 CASCADE;
-NOTICE:  drop cascades to 27 other objects
-DETAIL:  drop cascades to function alt_func3(integer)
-drop cascades to function alt_agg3(integer)
-drop cascades to function alt_func4(integer)
-drop cascades to function alt_func2(integer)
-drop cascades to function alt_agg4(integer)
-drop cascades to function alt_agg2(integer)
-drop cascades to conversion alt_conv3
-drop cascades to conversion alt_conv4
-drop cascades to conversion alt_conv2
-drop cascades to operator @+@(integer,integer)
-drop cascades to operator @-@(integer,integer)
-drop cascades to operator family alt_opf3 for access method hash
-drop cascades to operator family alt_opc1 for access method hash
-drop cascades to operator family alt_opc2 for access method hash
-drop cascades to operator family alt_opf4 for access method hash
-drop cascades to operator family alt_opf2 for access method hash
-drop cascades to table alt_regress_1
-drop cascades to text search dictionary alt_ts_dict3
-drop cascades to text search dictionary alt_ts_dict4
-drop cascades to text search dictionary alt_ts_dict2
-drop cascades to text search configuration alt_ts_conf3
-drop cascades to text search configuration alt_ts_conf4
-drop cascades to text search configuration alt_ts_conf2
-drop cascades to text search template alt_ts_temp3
-drop cascades to text search template alt_ts_temp2
-drop cascades to text search parser alt_ts_prs3
-drop cascades to text search parser alt_ts_prs2
 DROP SCHEMA alt_nsp2 CASCADE;
-NOTICE:  drop cascades to 9 other objects
-DETAIL:  drop cascades to function alt_nsp2.alt_func2(integer)
-drop cascades to function alt_nsp2.alt_agg2(integer)
-drop cascades to conversion alt_conv2
-drop cascades to operator alt_nsp2.@-@(integer,integer)
-drop cascades to operator family alt_nsp2.alt_opf2 for access method hash
-drop cascades to text search dictionary alt_ts_dict2
-drop cascades to text search configuration alt_ts_conf2
-drop cascades to text search template alt_ts_temp2
-drop cascades to text search parser alt_ts_prs2
 DROP USER regress_alter_user1;
 DROP USER regress_alter_user2;
 DROP USER regress_alter_user3;
diff --git a/src/test/regress/expected/object_address.out b/src/test/regress/expected/object_address.out
index 700f261827..3ca5c764ca 100644
--- a/src/test/regress/expected/object_address.out
+++ b/src/test/regress/expected/object_address.out
@@ -39,7 +39,7 @@ CREATE TRANSFORM FOR int LANGUAGE SQL (
 CREATE PUBLICATION addr_pub FOR TABLE addr_nsp.gentable;
 CREATE SUBSCRIPTION addr_sub CONNECTION '' PUBLICATION bar WITH (connect = false, slot_name = NONE);
 WARNING:  tables were not subscribed, you will have to run ALTER SUBSCRIPTION ... REFRESH PUBLICATION to subscribe the tables
-CREATE STATISTICS addr_nsp.gentable_stat ON (a,b) FROM addr_nsp.gentable;
+CREATE STATISTICS addr_nsp.gentable_stat ON a, b FROM addr_nsp.gentable;
 -- test some error cases
 SELECT pg_get_object_address('stone', '{}', '{}');
 ERROR:  unrecognized object type "stone"
diff --git a/src/test/regress/expected/stats_ext.out b/src/test/regress/expected/stats_ext.out
index 92ac84ac67..4ccdf21a01 100644
--- a/src/test/regress/expected/stats_ext.out
+++ b/src/test/regress/expected/stats_ext.out
@@ -5,24 +5,49 @@
 SET max_parallel_workers = 0;
 SET max_parallel_workers_per_gather = 0;
 SET work_mem = '128kB';
+-- Verify failures
+CREATE STATISTICS tst;
+ERROR:  syntax error at or near ";"
+LINE 1: CREATE STATISTICS tst;
+                             ^
+CREATE STATISTICS tst ON a, b;
+ERROR:  syntax error at or near ";"
+LINE 1: CREATE STATISTICS tst ON a, b;
+                                     ^
+CREATE STATISTICS tst FROM sometab;
+ERROR:  syntax error at or near "FROM"
+LINE 1: CREATE STATISTICS tst FROM sometab;
+                              ^
+CREATE STATISTICS tst ON a, b FROM nonexistant;
+ERROR:  relation "nonexistant" does not exist
+CREATE STATISTICS tst ON a, b FROM pg_class;
+ERROR:  column "a" referenced in statistics does not exist
+CREATE STATISTICS tst ON relname, relname, relnatts FROM pg_class;
+ERROR:  duplicate column name in statistics definition
+CREATE STATISTICS tst ON relnatts + relpages FROM pg_class;
+ERROR:  only simple column references are allowed in CREATE STATISTICS
+CREATE STATISTICS tst ON (relpages, reltuples) FROM pg_class;
+ERROR:  only simple column references are allowed in CREATE STATISTICS
+CREATE STATISTICS tst (unrecognized) ON relname, relnatts FROM pg_class;
+ERROR:  unrecognized statistics type "unrecognized"
 -- Ensure stats are dropped sanely
 CREATE TABLE ab1 (a INTEGER, b INTEGER, c INTEGER);
-CREATE STATISTICS ab1_a_b_stats ON (a, b) FROM ab1;
+CREATE STATISTICS ab1_a_b_stats ON a, b FROM ab1;
 DROP STATISTICS ab1_a_b_stats;
 CREATE SCHEMA regress_schema_2;
-CREATE STATISTICS regress_schema_2.ab1_a_b_stats ON (a, b) FROM ab1;
+CREATE STATISTICS regress_schema_2.ab1_a_b_stats ON a, b FROM ab1;
 -- Let's also verify the pg_get_statisticsextdef output looks sane.
 SELECT pg_get_statisticsextdef(oid) FROM pg_statistic_ext WHERE stxname = 'ab1_a_b_stats';
-                       pg_get_statisticsextdef                       
----------------------------------------------------------------------
- CREATE STATISTICS regress_schema_2.ab1_a_b_stats ON (a, b) FROM ab1
+                      pg_get_statisticsextdef                      
+-------------------------------------------------------------------
+ CREATE STATISTICS regress_schema_2.ab1_a_b_stats ON a, b FROM ab1
 (1 row)
 
 DROP STATISTICS regress_schema_2.ab1_a_b_stats;
 -- Ensure statistics are dropped when columns are
-CREATE STATISTICS ab1_b_c_stats ON (b, c) FROM ab1;
-CREATE STATISTICS ab1_a_b_c_stats ON (a, b, c) FROM ab1;
-CREATE STATISTICS ab1_a_b_stats ON (a, b) FROM ab1;
+CREATE STATISTICS ab1_b_c_stats ON b, c FROM ab1;
+CREATE STATISTICS ab1_a_b_c_stats ON a, b, c FROM ab1;
+CREATE STATISTICS ab1_a_b_stats ON a, b FROM ab1;
 ALTER TABLE ab1 DROP COLUMN a;
 \d ab1
                 Table "public.ab1"
@@ -31,14 +56,14 @@ ALTER TABLE ab1 DROP COLUMN a;
  b      | integer |           |          | 
  c      | integer |           |          | 
 Statistics:
-    "public.ab1_b_c_stats" WITH (ndistinct, dependencies) ON (b, c)
+    "public"."ab1_b_c_stats" (ndistinct, dependencies) ON b, c FROM ab1
 
 DROP TABLE ab1;
 -- Ensure things work sanely with SET STATISTICS 0
 CREATE TABLE ab1 (a INTEGER, b INTEGER);
 ALTER TABLE ab1 ALTER a SET STATISTICS 0;
 INSERT INTO ab1 SELECT a, a%23 FROM generate_series(1, 1000) a;
-CREATE STATISTICS ab1_a_b_stats ON (a, b) FROM ab1;
+CREATE STATISTICS ab1_a_b_stats ON a, b FROM ab1;
 ANALYZE ab1;
 WARNING:  extended statistics "public.ab1_a_b_stats" could not be collected for relation public.ab1
 ALTER TABLE ab1 ALTER a SET STATISTICS -1;
@@ -60,24 +85,24 @@ CREATE SERVER extstats_dummy_srv FOREIGN DATA WRAPPER extstats_dummy_fdw;
 CREATE FOREIGN TABLE tststats.f (a int, b int, c text) SERVER extstats_dummy_srv;
 CREATE TABLE tststats.pt (a int, b int, c text) PARTITION BY RANGE (a, b);
 CREATE TABLE tststats.pt1 PARTITION OF tststats.pt FOR VALUES FROM (-10, -10) TO (10, 10);
-CREATE STATISTICS tststats.s1 ON (a, b) FROM tststats.t;
-CREATE STATISTICS tststats.s2 ON (a, b) FROM tststats.ti;
+CREATE STATISTICS tststats.s1 ON a, b FROM tststats.t;
+CREATE STATISTICS tststats.s2 ON a, b FROM tststats.ti;
 ERROR:  relation "ti" is not a table, foreign table, or materialized view
-CREATE STATISTICS tststats.s3 ON (a, b) FROM tststats.s;
+CREATE STATISTICS tststats.s3 ON a, b FROM tststats.s;
 ERROR:  relation "s" is not a table, foreign table, or materialized view
-CREATE STATISTICS tststats.s4 ON (a, b) FROM tststats.v;
+CREATE STATISTICS tststats.s4 ON a, b FROM tststats.v;
 ERROR:  relation "v" is not a table, foreign table, or materialized view
-CREATE STATISTICS tststats.s5 ON (a, b) FROM tststats.mv;
-CREATE STATISTICS tststats.s6 ON (a, b) FROM tststats.ty;
+CREATE STATISTICS tststats.s5 ON a, b FROM tststats.mv;
+CREATE STATISTICS tststats.s6 ON a, b FROM tststats.ty;
 ERROR:  relation "ty" is not a table, foreign table, or materialized view
-CREATE STATISTICS tststats.s7 ON (a, b) FROM tststats.f;
-CREATE STATISTICS tststats.s8 ON (a, b) FROM tststats.pt;
-CREATE STATISTICS tststats.s9 ON (a, b) FROM tststats.pt1;
+CREATE STATISTICS tststats.s7 ON a, b FROM tststats.f;
+CREATE STATISTICS tststats.s8 ON a, b FROM tststats.pt;
+CREATE STATISTICS tststats.s9 ON a, b FROM tststats.pt1;
 DO $$
 DECLARE
 	relname text := reltoastrelid::regclass FROM pg_class WHERE oid = 'tststats.t'::regclass;
 BEGIN
-	EXECUTE 'CREATE STATISTICS tststats.s10 ON (a, b) FROM ' || relname;
+	EXECUTE 'CREATE STATISTICS tststats.s10 ON a, b FROM ' || relname;
 EXCEPTION WHEN wrong_object_type THEN
 	RAISE NOTICE 'stats on toast table not created';
 END;
@@ -158,20 +183,8 @@ EXPLAIN (COSTS off)
          ->  Seq Scan on ndistinct
 (5 rows)
 
--- unknown column
-CREATE STATISTICS s10 ON (unknown_column) FROM ndistinct;
-ERROR:  column "unknown_column" referenced in statistics does not exist
--- single column
-CREATE STATISTICS s10 ON (a) FROM ndistinct;
-ERROR:  extended statistics require at least 2 columns
--- single column, duplicated
-CREATE STATISTICS s10 ON (a,a) FROM ndistinct;
-ERROR:  duplicate column name in statistics definition
--- two columns, one duplicated
-CREATE STATISTICS s10 ON (a, a, b) FROM ndistinct;
-ERROR:  duplicate column name in statistics definition
 -- correct command
-CREATE STATISTICS s10 ON (a, b, c) FROM ndistinct;
+CREATE STATISTICS s10 ON a, b, c FROM ndistinct;
 ANALYZE ndistinct;
 SELECT stxkind, stxndistinct
   FROM pg_statistic_ext WHERE stxrelid = 'ndistinct'::regclass;
@@ -352,7 +365,6 @@ EXPLAIN (COSTS off)
    ->  Seq Scan on ndistinct
 (3 rows)
 
-DROP TABLE ndistinct;
 -- functional dependencies tests
 CREATE TABLE functional_dependencies (
     filler1 TEXT,
@@ -389,7 +401,7 @@ EXPLAIN (COSTS OFF)
 (2 rows)
 
 -- create statistics
-CREATE STATISTICS func_deps_stat WITH (dependencies) ON (a, b, c) FROM functional_dependencies;
+CREATE STATISTICS func_deps_stat (dependencies) ON a, b, c FROM functional_dependencies;
 ANALYZE functional_dependencies;
 EXPLAIN (COSTS OFF)
  SELECT * FROM functional_dependencies WHERE a = 1 AND b = '1';
@@ -432,7 +444,7 @@ EXPLAIN (COSTS OFF)
 (2 rows)
 
 -- create statistics
-CREATE STATISTICS func_deps_stat WITH (dependencies) ON (a, b, c) FROM functional_dependencies;
+CREATE STATISTICS func_deps_stat (dependencies) ON a, b, c FROM functional_dependencies;
 ANALYZE functional_dependencies;
 EXPLAIN (COSTS OFF)
  SELECT * FROM functional_dependencies WHERE a = 1 AND b = '1';
@@ -456,4 +468,3 @@ EXPLAIN (COSTS OFF)
 (5 rows)
 
 RESET random_page_cost;
-DROP TABLE functional_dependencies;
diff --git a/src/test/regress/sql/alter_generic.sql b/src/test/regress/sql/alter_generic.sql
index 88e8d7eb86..342f82856e 100644
--- a/src/test/regress/sql/alter_generic.sql
+++ b/src/test/regress/sql/alter_generic.sql
@@ -438,8 +438,8 @@ DROP OPERATOR FAMILY alt_opf18 USING btree;
 --
 SET SESSION AUTHORIZATION regress_alter_user1;
 CREATE TABLE alt_regress_1 (a INTEGER, b INTEGER);
-CREATE STATISTICS alt_stat1 ON (a, b) FROM alt_regress_1;
-CREATE STATISTICS alt_stat2 ON (a, b) FROM alt_regress_1;
+CREATE STATISTICS alt_stat1 ON a, b FROM alt_regress_1;
+CREATE STATISTICS alt_stat2 ON a, b FROM alt_regress_1;
 
 ALTER STATISTICS alt_stat1 RENAME TO alt_stat2;   -- failed (name conflict)
 ALTER STATISTICS alt_stat1 RENAME TO alt_stat3;   -- failed (name conflict)
@@ -448,8 +448,9 @@ ALTER STATISTICS alt_stat2 OWNER TO regress_alter_user3;  -- OK
 ALTER STATISTICS alt_stat2 SET SCHEMA alt_nsp2;    -- OK
 
 SET SESSION AUTHORIZATION regress_alter_user2;
-CREATE STATISTICS alt_stat1 ON (a, b) FROM alt_regress_1;
-CREATE STATISTICS alt_stat2 ON (a, b) FROM alt_regress_1;
+CREATE TABLE alt_regress_2 (a INTEGER, b INTEGER);
+CREATE STATISTICS alt_stat1 ON a, b FROM alt_regress_2;
+CREATE STATISTICS alt_stat2 ON a, b FROM alt_regress_2;
 
 ALTER STATISTICS alt_stat3 RENAME TO alt_stat4;    -- failed (not owner)
 ALTER STATISTICS alt_stat1 RENAME TO alt_stat4;    -- OK
@@ -572,12 +573,13 @@ SELECT nspname, prsname
 ---
 --- Cleanup resources
 ---
+set client_min_messages to warning; -- suppress cascade notices
+
 DROP FOREIGN DATA WRAPPER alt_fdw2 CASCADE;
 DROP FOREIGN DATA WRAPPER alt_fdw3 CASCADE;
 
 DROP LANGUAGE alt_lang2 CASCADE;
 DROP LANGUAGE alt_lang3 CASCADE;
-DROP LANGUAGE alt_lang4 CASCADE;
 
 DROP SCHEMA alt_nsp1 CASCADE;
 DROP SCHEMA alt_nsp2 CASCADE;
diff --git a/src/test/regress/sql/object_address.sql b/src/test/regress/sql/object_address.sql
index 8a738e20d6..f25ed735e1 100644
--- a/src/test/regress/sql/object_address.sql
+++ b/src/test/regress/sql/object_address.sql
@@ -41,7 +41,7 @@ CREATE TRANSFORM FOR int LANGUAGE SQL (
 	TO SQL WITH FUNCTION int4recv(internal));
 CREATE PUBLICATION addr_pub FOR TABLE addr_nsp.gentable;
 CREATE SUBSCRIPTION addr_sub CONNECTION '' PUBLICATION bar WITH (connect = false, slot_name = NONE);
-CREATE STATISTICS addr_nsp.gentable_stat ON (a,b) FROM addr_nsp.gentable;
+CREATE STATISTICS addr_nsp.gentable_stat ON a, b FROM addr_nsp.gentable;
 
 -- test some error cases
 SELECT pg_get_object_address('stone', '{}', '{}');
diff --git a/src/test/regress/sql/stats_ext.sql b/src/test/regress/sql/stats_ext.sql
index 72c7659c4b..4050f33c08 100644
--- a/src/test/regress/sql/stats_ext.sql
+++ b/src/test/regress/sql/stats_ext.sql
@@ -7,13 +7,24 @@ SET max_parallel_workers = 0;
 SET max_parallel_workers_per_gather = 0;
 SET work_mem = '128kB';
 
+-- Verify failures
+CREATE STATISTICS tst;
+CREATE STATISTICS tst ON a, b;
+CREATE STATISTICS tst FROM sometab;
+CREATE STATISTICS tst ON a, b FROM nonexistant;
+CREATE STATISTICS tst ON a, b FROM pg_class;
+CREATE STATISTICS tst ON relname, relname, relnatts FROM pg_class;
+CREATE STATISTICS tst ON relnatts + relpages FROM pg_class;
+CREATE STATISTICS tst ON (relpages, reltuples) FROM pg_class;
+CREATE STATISTICS tst (unrecognized) ON relname, relnatts FROM pg_class;
+
 -- Ensure stats are dropped sanely
 CREATE TABLE ab1 (a INTEGER, b INTEGER, c INTEGER);
-CREATE STATISTICS ab1_a_b_stats ON (a, b) FROM ab1;
+CREATE STATISTICS ab1_a_b_stats ON a, b FROM ab1;
 DROP STATISTICS ab1_a_b_stats;
 
 CREATE SCHEMA regress_schema_2;
-CREATE STATISTICS regress_schema_2.ab1_a_b_stats ON (a, b) FROM ab1;
+CREATE STATISTICS regress_schema_2.ab1_a_b_stats ON a, b FROM ab1;
 
 -- Let's also verify the pg_get_statisticsextdef output looks sane.
 SELECT pg_get_statisticsextdef(oid) FROM pg_statistic_ext WHERE stxname = 'ab1_a_b_stats';
@@ -21,9 +32,9 @@ SELECT pg_get_statisticsextdef(oid) FROM pg_statistic_ext WHERE stxname = 'ab1_a
 DROP STATISTICS regress_schema_2.ab1_a_b_stats;
 
 -- Ensure statistics are dropped when columns are
-CREATE STATISTICS ab1_b_c_stats ON (b, c) FROM ab1;
-CREATE STATISTICS ab1_a_b_c_stats ON (a, b, c) FROM ab1;
-CREATE STATISTICS ab1_a_b_stats ON (a, b) FROM ab1;
+CREATE STATISTICS ab1_b_c_stats ON b, c FROM ab1;
+CREATE STATISTICS ab1_a_b_c_stats ON a, b, c FROM ab1;
+CREATE STATISTICS ab1_a_b_stats ON a, b FROM ab1;
 ALTER TABLE ab1 DROP COLUMN a;
 \d ab1
 DROP TABLE ab1;
@@ -32,7 +43,7 @@ DROP TABLE ab1;
 CREATE TABLE ab1 (a INTEGER, b INTEGER);
 ALTER TABLE ab1 ALTER a SET STATISTICS 0;
 INSERT INTO ab1 SELECT a, a%23 FROM generate_series(1, 1000) a;
-CREATE STATISTICS ab1_a_b_stats ON (a, b) FROM ab1;
+CREATE STATISTICS ab1_a_b_stats ON a, b FROM ab1;
 ANALYZE ab1;
 ALTER TABLE ab1 ALTER a SET STATISTICS -1;
 -- partial analyze doesn't build stats either
@@ -55,20 +66,20 @@ CREATE FOREIGN TABLE tststats.f (a int, b int, c text) SERVER extstats_dummy_srv
 CREATE TABLE tststats.pt (a int, b int, c text) PARTITION BY RANGE (a, b);
 CREATE TABLE tststats.pt1 PARTITION OF tststats.pt FOR VALUES FROM (-10, -10) TO (10, 10);
 
-CREATE STATISTICS tststats.s1 ON (a, b) FROM tststats.t;
-CREATE STATISTICS tststats.s2 ON (a, b) FROM tststats.ti;
-CREATE STATISTICS tststats.s3 ON (a, b) FROM tststats.s;
-CREATE STATISTICS tststats.s4 ON (a, b) FROM tststats.v;
-CREATE STATISTICS tststats.s5 ON (a, b) FROM tststats.mv;
-CREATE STATISTICS tststats.s6 ON (a, b) FROM tststats.ty;
-CREATE STATISTICS tststats.s7 ON (a, b) FROM tststats.f;
-CREATE STATISTICS tststats.s8 ON (a, b) FROM tststats.pt;
-CREATE STATISTICS tststats.s9 ON (a, b) FROM tststats.pt1;
+CREATE STATISTICS tststats.s1 ON a, b FROM tststats.t;
+CREATE STATISTICS tststats.s2 ON a, b FROM tststats.ti;
+CREATE STATISTICS tststats.s3 ON a, b FROM tststats.s;
+CREATE STATISTICS tststats.s4 ON a, b FROM tststats.v;
+CREATE STATISTICS tststats.s5 ON a, b FROM tststats.mv;
+CREATE STATISTICS tststats.s6 ON a, b FROM tststats.ty;
+CREATE STATISTICS tststats.s7 ON a, b FROM tststats.f;
+CREATE STATISTICS tststats.s8 ON a, b FROM tststats.pt;
+CREATE STATISTICS tststats.s9 ON a, b FROM tststats.pt1;
 DO $$
 DECLARE
 	relname text := reltoastrelid::regclass FROM pg_class WHERE oid = 'tststats.t'::regclass;
 BEGIN
-	EXECUTE 'CREATE STATISTICS tststats.s10 ON (a, b) FROM ' || relname;
+	EXECUTE 'CREATE STATISTICS tststats.s10 ON a, b FROM ' || relname;
 EXCEPTION WHEN wrong_object_type THEN
 	RAISE NOTICE 'stats on toast table not created';
 END;
@@ -113,20 +124,8 @@ EXPLAIN (COSTS off)
 EXPLAIN (COSTS off)
  SELECT COUNT(*) FROM ndistinct GROUP BY b, c, d;
 
--- unknown column
-CREATE STATISTICS s10 ON (unknown_column) FROM ndistinct;
-
--- single column
-CREATE STATISTICS s10 ON (a) FROM ndistinct;
-
--- single column, duplicated
-CREATE STATISTICS s10 ON (a,a) FROM ndistinct;
-
--- two columns, one duplicated
-CREATE STATISTICS s10 ON (a, a, b) FROM ndistinct;
-
 -- correct command
-CREATE STATISTICS s10 ON (a, b, c) FROM ndistinct;
+CREATE STATISTICS s10 ON a, b, c FROM ndistinct;
 
 ANALYZE ndistinct;
 
@@ -202,8 +201,6 @@ EXPLAIN (COSTS off)
 EXPLAIN (COSTS off)
  SELECT COUNT(*) FROM ndistinct GROUP BY a, d;
 
-DROP TABLE ndistinct;
-
 -- functional dependencies tests
 CREATE TABLE functional_dependencies (
     filler1 TEXT,
@@ -233,7 +230,7 @@ EXPLAIN (COSTS OFF)
  SELECT * FROM functional_dependencies WHERE a = 1 AND b = '1' AND c = 1;
 
 -- create statistics
-CREATE STATISTICS func_deps_stat WITH (dependencies) ON (a, b, c) FROM functional_dependencies;
+CREATE STATISTICS func_deps_stat (dependencies) ON a, b, c FROM functional_dependencies;
 
 ANALYZE functional_dependencies;
 
@@ -259,7 +256,7 @@ EXPLAIN (COSTS OFF)
  SELECT * FROM functional_dependencies WHERE a = 1 AND b = '1' AND c = 1;
 
 -- create statistics
-CREATE STATISTICS func_deps_stat WITH (dependencies) ON (a, b, c) FROM functional_dependencies;
+CREATE STATISTICS func_deps_stat (dependencies) ON a, b, c FROM functional_dependencies;
 
 ANALYZE functional_dependencies;
 
@@ -270,4 +267,3 @@ EXPLAIN (COSTS OFF)
  SELECT * FROM functional_dependencies WHERE a = 1 AND b = '1' AND c = 1;
 
 RESET random_page_cost;
-DROP TABLE functional_dependencies;